Internal scarring, peridural and perineural fibrosis and adhesions after spinal surgery are well known and undesired side effects of said surgery. These conditions lead to a high percentage to pain, motion difficulties and often to the need for additional surgery. The use of a gel comprising carboxymethylcellulose and polyethylene oxide for the reduction of epidural adhesions after spinal surgery is disclosed in Kim et al: “Reduction in leg pain and lower-extremity weakness with Oxiplex/SP Gel for 1 year after laminectomy, laminotomy, and discectomy. Neurosurg Focus” 17(1): Clinical Pearl 1: 1-6, 2004); Porchet et al: “Inhibition of epidural fibrosis with ADCON-L: effect on clinical outcome one year following re-operation for recurrent lumbar radiculopathy.” Neurol Res 21 (Suppl 1): 51-S60, (1999); and, Ross et al: “Association between peridural scar and recurrent radicular pain after lumbar discectomy: magnetic resonance evaluation. ADCON-L European Study Group.” Neurosurgery 38:855-863, (1996). In these examples, a gel is distributed in an uncontrolled manner in the application area and once applied, the gel distribution cannot be easily manipulated or corrected. Further, these anti-adhesion gels have limited success as a barrier and have undefined layer thickness. These anti-adhesion gels have low hemostatic properties, if any at all, and provide no wound healing support functions and do not direct cell growth and tissue regeneration. There are even reports of increased rates of CSF (cerebro spinal fluid) leaks accruing in conjunction with the use of ADCON-L (Hieb, L. D. & Stevens, D. L. (2001). Spontaneous postoperative cerebrospinal fluid leaks following application of anti-adhesion barrier gel: case report and review of the literature. Spine, 26(7), 748-751; Kuhn, J., Hofmann, B., Knitelius, H. O., Coenen, H. H., & Bewermeyer, H. (2005). Bilateral subdural haematomata and lumbar pseudomeningocele due to a chronic leakage of liquor cerebrospinalis after a lumbar discectomy with the application of ADCON-L gel. J Neurol Neurosurg Psychiatry, 76(7), 1031-1033; Le, A. X., Rogers, D. E., Dawson, E. G., Kropf, M. A., De Grange, D. A., & Delamarter, R. B. (2001). Unrecognized durotomy after lumbar discectomy: a report of four cases associated with the use of ADCON-L. Spine, 26(1), 115-7; discussion 118.)
One commercially available anti-adhesion product is DURAGEN PLUS. The DURAGEN PLUS barrier, which is of bovine origin, is not very shape stable, which means that its shape and position is difficult to correct after application. Further, the DURAGEN PLUS barrier does not have a high tensile strength and elasticity. And due to the fact that the DURAGEN PLUS barrier is porous it is consequently not fluid-tight (impermeable to fluids) and therefore has limited success as a barrier function. Also, DURAGEN PLUS absorbs blood which can results in fibrin bands that play a key role in the pathogenesis of adhesion formations and its porous structure promotes non-directed cell in-growth which may also contribute to uncontrolled fibrotic tissue formation and to adhesions.
Consequently, a strong need exists for a new system for directed and controlled tissue regeneration to prevent post-surgical or post-traumatic peridural and perineural adhesion formation in the tissue healing and regeneration process following surgical and traumatic injuries which does not absorb blood, which supports the remodeling, regeneration, and the wound healing process, which directs the growth and the in-growth of cells, and which acts effectively as a biofunctional separation layer.
Thus, it is an object of the present invention to provide a new method for preventing post-surgical or post-traumatic peridural or perineural adhesion and fibrosis, and directing cell in-growth and controlling tissue regeneration by using a biofunctional collagen foil matrix to cover and separate spinal column tissues.